Metal compound/protonic acid containing electrically conductive compositions and methods for their preparation

ABSTRACT

Compositions and methods are described that relate to the use of reaction products of metal compounds and protonic acids for plasticizing and neutralizing acidic, protonated compositions comprising substituted and unsubstituted polyanilines and co-polymers and or mixtures thereof; and for reducing the percolation threshold for conductivity in blends with insulating bulk polymers.

This is a division of application Ser. No. 07/927,858 filed Aug. 11,1992, now U.S. Pat. No. 5,340,499.

FIELD OF THE INVENTION

This invention relates generally to conducting polymer compositions, andmore particularly relates to electrically conductive compositions andshaped articles, such as parts, containers, fibers, tapes, films andcoatings and the like, from polyanilines and blends thereof; and tomethods of forming and use of the same compositions and conductivearticles. More specifically, this invention relates to the use ofreaction products of metal compounds and protonic acids as plasticizers;and for reducing the percolation threshold for the onset of conductivityin blends comprising polyanilines and insulating bulk polymers; and forneutralizing acidic, protonated polyaniline compositions.

BACKGROUND OF THE INVENTION

Electrically conductive, thermoplastic polymer compounds are ofincreased practical interest, for instance, for packaging electronicinstruments and parts, and to solve a wide range of static discharge,electrostatic dissipation and electromagnetic shielding problems. Often,such compounds are made by mixing, for example, carbon black, stainlesssteel fibers, silver or aluminum flakes or Nickel-coated fibers withinsulating bulk thermoplastics such as polystyrene, polyolefins, nylons,polycarbonate, acrylonitrile butadiene styrene co-polymers (ABS), andthe like. These filled compounds are subsequently processed into desiredshapes and articles by common plastics processing methods such asextrusion, injection or blow molding and the like. Major problemsrelated to the above filled thermoplastic compounds are that processingof these materials is not trivial and is often associated with excessivemachine wear, and that the final compounds frequently exhibitundesirable mechanical properties such as brittleness and a reducedelongation to break in comparison with the corresponding properties ofthe untilled matrix polymer.

More recently, there has been an increased interest in replacing suchcarbon black or metal-filled compounds with intrinsically electricallyconductive polymers and their blends with common insulating polymers.The latter systems are believed to be more cost competitive, easier toprocess and to exhibit desirable mechanical properties. Among thevarious conductive polymers, the polyanilines in particular haveattracted attention because of their excellent environmental stabilityand their low production costs.

Polyaniline is well known in the art, and the preparation of theelectrically conductive form of this polymer based on, for example,contacting polyanilines with protonic acids has been described. Green,A. G., and Woodhead, A. E., "Aniline-black and Allied Compounds, Part1," J. Chem. Soc., Vol. 101, pp. 1117 (1912); Kobayashi, et al.,Electrochemical Reactions . . . of Polyaniline Film-Coated Electrodes,J. Electroanl. Chem., Vol. 177, pp. 281-91 (1984); U.S. Pat. Nos.3,963,498, 4,025,463 and 4,983,322. Typical examples of such describedprotonic acids are HCL, H₂ SO₄, sulfonic acids of the type R₁ --SO₃ H,phosphoric acids, etc. Chiang, J. -C. and MacDiarmid, A. G.,"Polyaniline: Protonic Acid Doping of the Emeraldine Form to theMetallic Regime", Synthetic Metals, Vol. 13, p. 196 (1986); Salaneck, W.R. et al., "A Two-Dimensional-Surface "State" Diagram for Polyaniline",Synthetic Metals, Vol. 13, p. 297 (1986). Such acids form complexes withpolyaniline, which, generally, exhibit electrical conductivities of 10⁻³S/cm or more. Their electrical properties make these so-called "doped"polyanilines and their blends and compounds with common insulating bulkpolymers suitable for a variety of the antistatic and shieldingapplications that are currently served by metal or carbon black filledsystems.

Processing of polyanilines has been described in several patents andpatent applications. In U.S. Pat. No. 5,006,278 a conductive product isdescribed which has been made by mixing a solvent, a doping agent and apolyaniline, whereafter the solvent has been removed by evaporation. InPCT Publication No. WO 9013601 a polymer mixture is prepared by mixing asuitable solvent with a mixture of polyaniline and a multi-sulphonicacid, used as a doping agent, whereafter the solvent is evaporated.According to this specification, the doping is generally carried out at20°-25° C. it is described that the doping can be carried out as aheterogeneous reaction, followed by dissolution of the mixture in asuitable solvent. The processing into a final shape is carried out inthe presence of a solvent. (p. 15, 1.23).

PCT Publication No. WO 9010297, U.S. Pat. No. 5,002,700 and EuropeanPatent Publication No. EP 152 632 describe the use of dodecylbenzenesulphonic acid as a doping agent for polyaniline, PCT Publication No. WO9001775 describes a multi-sulphonic acid as a doping agent forpolyaniline with the advantage of better thermal stability compared withother sulphonic acids. In the examples of this specification, the dopingof polyaniline has been carried out in a suspension of polyaniline andthe sulphonic acid in an aqueous solution of formic acid. In none of theexamples of the above mentioned patent specifications, however, haveadequate methods been described for melt processing of polyanilinecompositions.

Melt processing of compounds comprising conductive polyanilines, hastypically been executed by mechanically mixing the components, where theconductive polyaniline is in the solid form and the matrix polymer inits molten form before shaping the blend into the desired article.Generally, the blends obtained exhibit varying conductivity, are ofnon-homogeneous quality and of poor mechanical properties and, generallyshow a high percolation threshold for the onset of electricalconductivity.

It has indeed been suggested, that certain polyaniline-based systems andblends may be processed using standard polymer processing techniques.For example, in Plastics Technology 37 (1991):9 pp. 19-20 is describedthe use of protonated, conductive polyanilines to impart conductivity tomixtures with common insulating thermoplastic polymers such as nylonsand poly(vinylchloride). In this application, however, the conductivepolyaniline is in the form of solid, intractable particles, which, muchlike carbon black, are dispersed in the non-conducting matrix, which isin its molten form. Melt-processing of these compounds requires specialmelt dispersion techniques; European Patent Publication Nos. EP 168 620and 168 621. A relatively high content of conductive polyaniline isrequired to reach desirable levels of conductivity in the blends withinsulating polymers; or, in other words, the percolation threshold forthe onset of conductivity is relatively high. Thus, in theaforementioned blends of solid polyaniline particles dispersed inpoly(vinylchloride) a percolation threshold existed of about at least13% w/w of the conductive polyaniline. Such a high content of conductivepolyaniline particles is not desirable, because it is not economicaland, in addition, may substantially alter the mechanical properties ofthe blend in comparison with those of the pure matrix polymer.

An improved method of making conductive polyaniline compositions hasbeen described in Finnish Patent Application 915 760. According to thisapplication, polyaniline, or derivatives thereof, and an excess of anorganic protonic acid are mechanically mixed. The liquid-like mixture orsuspension is subsequently thermally solidified between 40°-250° C. in amixer. As a result, a dry, solid composition, in the form of a granulatecomprising protonic acid-doped polyaniline is obtained. The solidpolyaniline-protonic acid complex can subsequently be mixed withinsulting thermoplastic polymers and formed into parts of desired shapesusing standard polymer melt-processing techniques. Improved visualsurface characteristics and lower percolation thresholds for theconductivity were observed for parts made according to this method.However, as stated above, an excess of acid is used in the technique.The latter generally is unacceptable from a processing, application andenvironmental point of view. The excess acid, of course, can be removed,but this process is tedious and uneconomical, and limits the scope ofthe products that can be manufactured.

In a publication in Synthetic Metals (Vol. 48 (1992) pp. 91-97) aredescribed blends that exhibit much lower percolation thresholds,sometimes even below 1% w/w, of conductive polyaniline and a widevariety of non-conducting matrix polymers, such as polyethylenes,poly(vinylchloride), polystyrene, nylons, and the like;poly(methylmethacrylate), polycarbonate, acrylonitrile butadiene styrenecopolymers (ABS), and the like. However, invariably, the compositionsthat exhibit such low percolation thresholds are made from solutions ofthe conductive polyaniline and the matrix polymers, which isuneconomical, and limits the use to fabrication of products such asfilm, coatings and fibers.

Thus, clearly, a need exists for electrically conductive polyanilinecompositions that can be processed from the melt, and for polyanilineblends with, for example, insulating bulk polymers that exhibit a lowpercolation threshold, and do not contain an excess of protonic acid,i.e. are neutral or only slightly acidic, and for economical methods tofabricate articles from the melt of such compositions.

SUMMARY OF THE INVENTION

It is accordingly an object of the present invention to provideelectrically conductive compositions containing polyaniline and thereaction products of metal compounds and protonic acids, that can beprocessed from the melt and that are approximately neutral or onlyslightly acidic.

It is additionally an object of the present invention to provideelectrically conductive blends and articles that comprise polyanilineand further comprise the reaction products of metal compounds andprotonic acids, that can be processed from the melt and that display alow percolation threshold for the onset of electrical conductivity.

Another object of the present invention is to provide a method to make,from the melt, electrically conductive compounds and articles comprisingpolyaniline that are neutral or only slightly acidic by the addition ofthe reaction products of metal compounds and protonic acids.

It is still another object of the present invention to provide a methodto make, from the melt, electrically conductive compounds and articlescomprising polyaniline that display a low percolation threshold by theaddition of the reaction products of metal compounds and protonic acidsto blends of said polyaniline and insulating matrix polymers.

Still another object of the present invention is to provide a method tomake, from the melt, electrically conductive compounds and articlescomprising polyaniline that display a low percolation threshold by theaddition of metal compounds, that form a fluid composition with protonicacids, to blends of acidic polyaniline compositions and insulatingmatrix polymers.

It is still yet another object of the present invention to provideshaped articles, fibers, coatings, films, tapes and the like fromelectrically conductive polyaniline and blends of electricallyconductive polyaniline with insulating bulk polymers and pre-polymers.

Additional objects, advantages and novel features of the invention willbe set forth, in part, in the description which follows, and, in part,will become apparent to those skilled in the art on examination of thefollowing, or may be learned by practice of the invention. The objectsand advantages of the invention may be realized and attained by means ofthe instrumentalities and combinations particularly pointed out in theappended claims.

In one aspect of the invention, neutral, or only slightly acid,melt-processable polyaniline compositions are fabricated; for example,an amount of the metal oxide ZnO is contacted at 150° C. with 2 moles ofdodecylbenzene sulfonic acid to yield a fluid reaction product. Thisfluid reaction product is mixed at 180° C. with the conductive saltcomplex of polyaniline and dodecylbenzene sulfonic acid, and anessentially neutral, plasticized melt is formed, which is processed intouseful shapes such as, for example, films, fibers and pads, and thelike.

In another aspect of this invention, the above described melt of theconductive polyaniline-dodecylbenzene sulfonic acid complex and thereaction product of the ZnO and the dodecylbenzene sulfonic acid isblended at elevated temperatures with molten insulating matrix polymers,such as, for example polyethylene. Surprisingly, the inventors havefound that compositions are obtained that can be processed from the meltand that display unexpectedly low percolation thresholds for electricalconductivity.

DETAILED DESCRIPTION OF THE INVENTION Definitions

It must be noted that, as used in the specifications and the appendedclaims, the singular forms "a", "an" and "the" include plural referentsunless the context clearly dictates otherwise. Thus, for example,reference to "a polyaniline" includes mixtures of polyanilines,reference to "a reaction product" includes mixtures of two or morereaction products, reference to "a metal compound" includes mixtures oftwo or more metal compounds, reference to "an acid" includes mixtures oftwo or more acids, and the like.

When the term "polyaniline" is used in this application, it is usedgenerically to include substituted and unsubstituted polyanilines andpolyaniline copolymers, and mixtures thereof, unless the context isclear that only the specific nonsubstituted form is intended.

As used hereinafter, the "percolation threshold" is defined as theweight fraction of conductive compound needed to impart a conductivityof 10⁻⁸ S/cm or more to a blend with an insulating matrix substrate.

The term "insulating" or "substantially non-conducting material" refersto materials that have an electrical conductivity of less than about10⁻¹⁰ S/cm.

The specification "approximately neutral or slightly acidic"compositions refer to compositions that impart to water after 24 hrsexposure a pH of between about 4 and 8.

The compositions of this invention typically include three or four typesof components.

(i) A substituted or unsubstituted polyaniline or co-polymers, ormixtures thereof;

(ii) A protonic acid solute that form salt complexes with thesubstituted or unsubstituted polyanilines or co-polymers or mixturesthereof and that have a conductivity greater than about 10⁻⁶ S/cm;

(iii) A metal compound that neutralizes protonic acids and forms areaction product with certain acids, having a softening temperature ofbelow about 300° C. The addition of this component effectuates thespecial eventuality described in this invention of neutralization,plasticization and/or percolation-threshold reduction in theaforementioned polyaniline compositions.

(iv) One or more optional organic substrate phases. This phase is aninsulating material, and can be one or more polymers or pre-polymers, ormixtures thereof, which is fluid during compounding or mixing with (i),(ii) and (iii) and/or during shaping into the conductive article.

Surprisingly, it has been discovered that, unlike the electricallyconductive compositions described in the prior art, materials can beprepared from the melt comprising polyaniline, substituted polyanilinesor co-polymers, or mixtures thereof, that are approximately neutral oronly slightly acidic; and that display a percolation threshold for theonset of conductivity in blends with insulating substrates as low asbelow 1% w/w.

The Polyaniline

One component in the present materials is substituted or unsubstitutedpolyaniline or a polyaniline copolymer as described in U.S. Pat. No.4,983,322, which by reference is incorporated herein in its entirety.

Particularly preferred for the use in the practice of this invention, isthe polyaniline that is derived from unsubstituted aniline.

In general, the polyanilines useful in the practice of this inventionare those which are of sufficiently high molecular weight to exhibithigh electrical conductivity, i.e. having a weight average molecularweight of more than 5,000 daltons. In general substituted andunsubstituted polyanilines and polyaniline copolymers will be of atleast 20 repeat units. In the preferred embodiments of the invention,the number of repeat units is at least about 25, and in the mostpreferred embodiments, the number of repeat units is at least about 50.

The polyaniline can be conveniently used in the practice of thisinvention in any of its physical forms. Illustrative of useful forms arethose described in U.S. Pat. No. 4,983,322, which by reference isincorporated herein in its entirety. For unsubstituted polyaniline,useful forms include leucoemeraldine, protoemeraldine, emeraldine,nigraniline and tolu-protoemeraldine forms. Useful polyanilines can beprepared through the use of chemical and electrochemical syntheticprocedures referred to, for example, in the above references.

The Protonic Acid

A second component of the compositions of the present invention is aprotonic acid that imparts a conductivity to the composition.

As used herein, a "protonic acid" is an acid that protonates thepolyaniline to form a salt complex with said polyaniline, which has aconductivity greater than about 10⁻⁶ S/cm. Preferred protonic acids arethose that protonate the polyaniline to form a salt complex, saidcomplex having an electrical conductivity of greater than about 10⁻³S/cm, and particularly preferred protonic acids are those that impart aconductivity of greater than about 0.1 S/cm to the salt complex withpolyaniline. Amongst these particularly preferred embodiments, mostpreferred are those embodiments in which said polyaniline salt complexhas a conductivity of greater than 10 S/cm.

Protonic acids are well known as dopants in the conductive polymer artas shown by the references to J. -C. Chiang and A. G. MacDiarmid; W. R.Salaneck et al.; U.S. Pat. No. 5,006,278; PCT Publication No. WO9013601; Synthetic Metals Vol. 48 (1992) pp. 91-97, noted above.

Metal Compound

The third component of the compositions of the present invention is ametal compound that generally neutralizes protonic acids and forms areaction product with certain acids having a softening temperature ofbelow about 300° C.

Surprisingly, it was discovered that

mixtures of certain metal compounds, such as, and in particular, theamphoteric metal oxide ZnO, and certain protonic acids, such as, forexample, dodecylbenzene sulfonic acid, form a fluid especially afterheating at elevated temperatures, e.g. above about 100° C.; and that

when the resulting fluid was mixed with an approximately neutralconductive salt complex of polyaniline and a protonic acid, anessentially neutral, plasticized melt was formed that could be directlyformed into useful conductive articles, such as fibers, films, parts andthe like; and that

when this melt was blended with molten insulating substrates,compositions were obtained that displayed unexpectedly low percolationthresholds for electrical conductivity.

Thus, in this instant the reaction product of the metal compound and theprotonic acid fulfils a special role of plasticizer and, in blends, apercolation-threshold reducing agent. It will become apparent from theexamples attached hereto that the latter effect is unusual, and cannotsimply be effected by the addition of most commonly availableplasticizers.

The metal compounds for use in the practice of this invention generallyare compounds that form condensation products with protonic acids andcan be oxides, hydroxides, halides, stearates, carbonates, palmitates,octoates, laurares, phenolares, maleares, octylthioglycolates, and thelike. Particularly preferred metal compounds for use in the presentinvention consist of the group of metal compounds comprising theelements Zn, Cu, Mg, Ba, Al, Ca, Ti, Fe, Zr, Cd, Pb and Sn. Amongst theparticularly preferred metal compounds for use in the present invention,the especially preferred compounds are the metal compounds comprisingthe elements Zn, Cu, Ca or Mg. Amongst the particularly preferred metalcompounds for use in the present invention, the most preferred compoundsare the metal compounds comprising the element Zn. In the preferredembodiment of the present invention, the metal compounds are selectedfrom the group consisting of oxides and hydroxides. In the particularlypreferred embodiment of the present invention the metal compounds areoxides. Amongst the particularly preferred metal oxides for use in thepresent invention is ZnO.

In the embodiments of the present invention, the certain protonic acidthat reacts with the aforementioned metal compound and is neutralized bythe above metal compound to form a reaction product having a softeningtemperature of below about 300° C., is selected from the groupconsisting of those of Formulas I and II: ##STR1## wherein:

"A" is sulphonic acid, selenic acid, phosphonic acid, boric acid or acarboxylic acid group; or hydrogen sulphate, hydrogen selenate orhydrogen phosphate;

"n" is an integer in the range of 0-5 inclusive;

"m" is an integer in the range of 0-4 inclusive, with the proviso thatthe sum of n+m is 5;

"R₁ " is an alkyl, alkenyl, alkoxy, alkanoyl, alkylthio, alkylthioalkylcontaining 1-20 carbon atoms; or alkylaryl, arylalkyl, alkylsulphinyl,alkoxyalkyl, alkylsulphonyl, alkoxycarbonyl, carboxylic acid, where thealkyl or alkoxy has from 0 to about 20 carbon atoms; or alkyl havingfrom 3-20 carbon atoms substituted with one or more sulphonic acid,carboxylic acid, halogen, nitro, cyano, diazo or epoxy moieties; or asubstituted or unsubstituted 3, 4, 5, 6, or 7 membered aromatic oralicyclic carbon ring, which ring may include one or more divalentheteroatoms of nitrogen, sulfur, sulfinyl, sulfonyl or oxygen such asthiophenyl, pyrolyl, furanyl, pyridinyl.

In addition to these monomeric acid forms, R₁ can be a polymericbackbone from which depend a plurality of acid functions "A". Examplesof polymeric acids include sulfonated polystyrene, sulfonatedpolyethylene and the like.

R is the same or different at each occurence and is an alkyl, alkenyl,alkoxy, cycloalkyl, cycloalkenyl, alkanoyl, alkylthio, aryloxy,alkylthioalkyl, alkylaryl, arylalkyl, alkylsulphinyl, alkoxyalkyl,alkylsulphonyl, aryl, arylthio, arylsulphinyl, alkoxycarbonyl,arylsulphonyl, carboxylic acid, halogen, cyano, or alkyl which has beensubstituted with one or more sulfonic acid, carboxylic acid, halogen,nitro, cyano, diazo or epoxy moieties; or any two R substitutent takentogether are an alkylene or alkenylene group completing a 3, 4, 5, 6 or7 membered aromatic or alicyclic carbon ring or multiples thereof whichring or rings may include one or more divalent heteroatoms of nitrogen,sulfur, sulfinyl, sulfonyl or oxygen. R typically has from about 1 toabout 20 carbons, especially 3 to 20 and more especially from about 8 to20 carbons.

Particularly preferred for use in the practice of this invention are theprotonic acids of formulae I and ! 1 wherein:

A is sulphonic acid;

n is the integer 1 or 2;

m is the integer 3 or 4, with the proviso that the sum n+m is 5;

R₁ is alkyl or alkoxy, having from 2 to about 14 carbon atoms, or analkyl having from 3 to about 12 carbon atoms substituted with one ormore halogen moieties;

R is alkyl or alkoxy, having from 4 to about 14, especially 12 carbonatoms, or alkyl substituted with one or more halogen moieties.

In the most preferred embodiments, the protonic acid that according tothe present invention is reacted with the metal compound isdodecylbenzene sulphonic acid.

Those skilled in the art of chemistry will be readily able to select theparticular combination of metal compounds and protonic acids that yielda reaction product with a softening temperature of below about 300° C.

It should be noted that the protonic acid that is used to form theconductive complex with the polyaniline can be different from, or thesame as the certain protonic acid that is used to form the reactionproduct with the metal compound.

In the event that an excess of a protonic acid of the component (ii) isused to form the electrically conductive complex with the polyaniline(i), the reaction product (iii) of the metal compound and the protonicacid may simply be formed by adding the metal compound to the acidic,protonated polyaniline composition. In this instant, the protonic acidof components (ii) and (iii) of the present invention are identical, andthe metal compound additionally fulfils a role as neutralizer.

The Substrate Phase

A fourth, optional, component of the compositions of this invention isthe substrate. This can be bulk oligomeric or polymeric or pre-polymericmaterials which can be transformed into a fluid (liquid or semisolid)form during processing so as to achieve the required intimate mixingwith the polyaniline, the protonic acids and the metal compound-acidreaction product. Illustrative of useful polymeric substrates arepolyethylenes, isotactic polypropylene, elastomers,styrene-butadiene-styrene (SBS) copolymers, polybutadiene, and the like,poly(vinylchloride), polystyrene, poly(vinylalcohol), poly(ethyleneterephthalate), nylons, such as nylon 6, nylon 6.6, nylon 12 and thelike; poly(methylmethacrylate), polycarbonate, acrylonitrile butadienestyrene copolymers (ABS), and the like. Generally, the substrate is asubstantially nonconductive material.

Overall Compositions

The proportions of materials of the present invention can vary widely,depending on the desired level of electrical conductivity and theapplication. However, the relative amounts of the polyaniline, protonicacid and metal compound is such that approximate neutrality or onlyslight acidity is achieved in the final composition; i.e. that when thematerials of the present inventions are exposed to water, the pH isbetween 3 and 8; more preferably between 4 and 8; and most preferablybetween 5 and 8.

Typically, the compositions of this invention include polyaniline,substituted polyaniline, copolymers and/or mixtures thereof, a protonicacid, the reaction product of a protonic acid and a metal compound, andan optional insulating substrate. The relative weight or volumeproportions of these materials strongly depend not only on the desiredconductivity, but also on the density, molecular weight and the numberof acid protons or functionality of the various components involved.Therefore, below are given general practical guidelines in the form ofmolar fractions and ratios for one of the preferredpolyaniline/acid/metal compound systems, namely that comprised ofunsubstituted polyaniline, dodecylbenzene sulfonic acid and ZnO.

In one embodiment of the present invention directed for use with thepreferred polyaniline/dodecylbenzene sulfonic acid/ZnO system, anapproximately neutral, or slightly acidic polyaniline-dodecylbenzenesulfonic acid salt complex is formed, wherein the molar ratio betweenacid protons and the aniline repeat unit is from about 0.2 to about 0.5,more preferably from about 0.3 to about 0.5. When mixed with thisneutral, or slightly acidic salt complex, the added reaction products ofthe metal compound and the protonic acid also are neutral or slightlyacidic. The molar ratio of said metal compound reaction products, basedon the element Zn, relative to said polyaniline-dodecylbenzene sulfonicacid complex, based on the aniline repeat unit, according to thisembodiment of the present invention ranges from about 0.2 to about 20,preferably from about 0.25 to 15, and most preferably from about 0.3 toabout 10.

In another embodiment of the present invention compositions can beprepared using highly acidic polyaniline-salt complexes, i.e. thosecomplexes containing an amount of acid or acids in excess of 0.5 molesof acid protons per aniline repeat unit. In this embodiment, thecomposition of the metal compound protonic acid reaction mixture needsto be altered and adjusted so that approximate neutrality or slightacidity of the final mixture is achieved after mixing with the acidicpolyaniline-salt complex. Thus, in this embodiment of the presentinvention, the amount of protonic acid that is reacted with the metalcompound is reduced by an amount of acid protons that is approximatelythe same as the excess amount used in the preparation of the acidicpolyaniline-salt complex. In a particular embodiment of the presentinvention, the excess amount of acid or acids used in the preparation ofthe polyaniline-salt complex is such that only the pure metal compoundwithout any additional acid is added to the mixture, and is reacted withthe excess acid to yield the plasticizing compound and, in blends withinsulating substrates, the percolation threshold reducing agent.Conversely, if in another embodiment of the present invention thepolyaniline-salt complex is prepared with a deficiency in acidicprotons, i.e. less than 0.3 mole per aniline repeat unit, the metalcompound-acid reaction mixture will contain an excess of acid, so thatafter mixing of the final blend approximate neutrality or only slightacidity is achieved.

In the above preferred embodiments the protonic acid is dodecylbenzenesulfonic acid and the metal compound is ZnO, which have normalequivalents of protons of 1 and 2, respectively. In other embodiments ofthe present invention acids and metal compounds may be used that havedifferent normal equivalents of protons. It will be appreciated to thoseskilled in the art of acid-base chemistry that the relative proportionsof the different acids and metal compounds need to be varied accordingto the normal equivalent of protons of the components to ensureneutrality or only slight acidity of the final mixture.

The amount of conductive polyaniline-salt complex in blend compositionscomprising insulating substrates may vary widely, and is dependent onthe desired level of conductivity. Hence, the content of thepolyaniline-salt complex according to this invention ranges from atleast about 0.05% by weight to about 90% by weight, preferably fromabout 0.1% by weight to about 40% by weight, and most preferably fromabout 0.5% by weight to about 20% by weight.

In addition to the polyaniline homopolymer or substituted anilinehomopolymers, copolymers, or mixtures thereof, a protonic acid, a metalcompound and a substrate, the compositions used in the present inventioncan include other optional components which either dissolve or do notdissolve in said compositions. The nature of such optional componentscan vary widely, and include those materials such as flame retardants,anti-oxidants, heat stabilizers, inorganic fillers, dyes and the like;which are known to those of skill in the art for inclusion in polymerarticles. The total of other materials that can be present is as much as98% of the total mixture, and being optional can be omitted altogether.Usually, for commercially attractive products these added components maymake up 2% to 50% by weight of the total final product.

The method of forming the electrically conductive compositions of thisinvention is not very critical and can vary widely. It is important,however, that at some stage the substrate be processed with thepolyaniline, protonic acid and metal compound in a fluid (liquid,semi-solid, or molten form) to assure proper intimate mixing. Otherwise,no special requirements are needed and common melt-processing techniquesknown to those ordinarily skilled in the art of polymer processing canbe applied, such as extrusion, kneading and the like.

Also, the sequence in which the different components are mixed togetheris not critical and may be varied widely. For example, the polyanilinesmay be first mixed with an excess of protonic acid to ensure homogeneousdoping. Subsequently, the metal compound may be added to neutralize thecomplex, and simultaneously form the reaction product with the excessamount of protonic acid, which fulfils the special role of plasticizerand the percolation-threshold reducing agent. The resulting mixture canbe directly processed from the melt in desirable shapes or be blendedwith the optional insulating substrate phase to yield the final blend ofthe present invention. Alternatively, the metal compound-protonic acidproduct is first prepared by common mixing methods, to yield theplasticizing and percolation-threshold reducing agent. This product,subsequently may be added to a separately prepared conductivepolyaniline-protonic acid complex; and the resulting mixture can bedirectly processed from the melt in desirable shapes or be blended withthe optional insulating substrate phase. Other mixing methods andsequences may be practiced within the scope of the present invention, ifso desired.

Typically, mixing and preparation of the metal compound-acid reactionproduct and blending with the polyaniline-salt complex is carried out aelevated temperatures, but below temperatures where thermal degradationcommences. Preferably, processing temperatures range from at least about40° C. to below about 300° C., and most preferably from at least about50° C. to below about 250° C.

Common manufacturing methods may be used to fabricate usefulelectrically conductive articles from the compositions of the presentinvention. It will be appreciated by those skilled in the art of polymerproduct manufacturing that a variety of technologies may be utilized,depending on the nature and shape of the desired article or product,such as melt-spinning, melt-blowing, injection molding, film casting,and the like.

The following specific examples are presented to illustrate theinvention and are not to be construed as limitations thereon.

EXAMPLE 1

0.2 g zinc oxide (ZnO, Aldrich) powder and 0.6 g liquid dodecylbenzenesulphonic acid (DBSA, Tokyo Kasei), (ZnO:DBSA=1:3 w/w), were mixed in adispersing mixer, whereafter the mixture was thermally solidified at150° C. using a screw-mixer. A white reaction product was obtained thatexhibited a melting temperature of about 115° C. The reaction productwas further transferred into a powder or a granulate using a grinder ora granulator, respectively.

A solid, acidic complex comprising polyaniline (PANI) and DBSA,PANI-DBSA, with a weight ratio (w/w) of PANI:DBSA=1:4, was prepared in ascrew mixer at 180° C. as described in FI Patent Application 915 760 andherein included as a reference.

0.8 g of the ZnO-DBSA reaction product, 0.8 g of the PANI-DBSA complexand 10.4 g polystyrene (PS, Neste Chemicals, Finland, SB 735) resin weremixed in an injection molding apparatus at 180° C. The obtained shapedarticle had a surface resistance of 500 kh and a surface pH of 7. Thetotal amount of the electrically active component, polyaniline, was only1.5 wt.-% of the total composition.

EXAMPLE 2

A 1:1 (w/w) mixture comprising acidic, solid PANI-DBSA complex and thereaction product of ZnO and DBSA, both prepared according to Example 1,was made by mechanical mixing. The resulting mixture was furthermelt-processed at 130° C. using a screw-mixer. The obtained compositionhad a surface resistance of 100 kΩ, exhibited excellent plasticizingproperties and was neutral.

EXAMPLE 3

1105 g acidic PANI-DBSA complex (1:2.5 w/w) and 1606 g of a dispersionof ZnO in DBSA (1:2.7, w/w) were mechanically mixed. During mixingevolution of heat was observed and the mixture solidified completely inabout 30-50 minutes. The as-formed solid, neutral composition had a darkgreen color, a surface resistance of 500 kΩ and exhibited good meltingcharacteristics.

EXAMPLE 4

400 g ZnO and 2880 g DBSA (1:7.2 w/w) were mixed in a blender. To thismixture, 720 g of the emeraldine base (EB) form of PANI was added andmixed. The resulting dark grey liquid mixture was solidified accordingto a process described in FI Patent Application 915 760 at 185° C. Theresulting solid was neutral, had a surface resistance of 500K Ω andexhibited good melting characteristics.

EXAMPLE 5

A 1:2.5 (w/w) complex of PANI-DBSA was prepared according to a processdescribed in FI Patent Application 915 760. A reaction product wasprepared by reacting 27 wt-% ZnO with 73 wt-% DBSA at 130° C. A blendwas prepared by mixing 2.4 g of a mixture containing 2.4 pads ZnO-DBSAreaction product and 3.5 pads of the PANI-DBSA complex and 9.6 gpolystyrene (Neste, SB 735). The mixture was injection molded at 170° C.The resulting injection molded article had a surface resistance of 30MΩand excellent surface appearance.

EXAMPLE 6

15 g of a 1:1.2 (w/w) PANI-DBSA complex was mechanically mixed with 15 gof the reaction product of ZnO and DBSA of Example 1. The resultingmixture was mixed at 130° C. using an apparatus as described in FIPatent Application 915 760. The resulting composition was neutral, hadgood plasticizing characteristics and had a surface resistance of 30kΩ.

EXAMPLE 7

5 g PANFEB and 15 g of the reaction product of ZnO and DBSA of Example 1was mixed according to Example 6. The resulting composition was neutraland had a surface resistance of 5MΩ.

EXAMPLE 8

25 wt-% of ZnO-DBSA (1:3, w/w) and 75 wt-% PANI-DBSA (1:4, w/w) weremixed at 150° C. The surface resistance of the resulting composition was3kΩ.

EXAMPLE 9

20 wt-% of ZnO-DBSA (1:3, w/w) and 80 wt-5 PANI-DBSA (1:2.5, w/w) weremixed at 150° C. The surface resistance of the resulting composition was200 Ω.

EXAMPLE 10

20 wt-% of the composition of Example 9 and 80 wt-% polystyrene. (Neste,SB 735) were mixed at 160° C. The surface resistance of the resultingblend was 500kΩ.

EXAMPLE 11

25 wt-% of the composition of Example 9 and 75 wt-% of polyethylene(Neste, NCPE 2220) were mixed at 160° C. The surface resistance of theresulting blend was 2MΩ.

EXAMPLE 12

50 wt-% of ZnO-DBSA (1:4, w/w) and 50 wt-% PANI-DBSA (1:4, w/w) weremixed at 150° C. The surface resistance of the resulting composition was2MΩ.

EXAMPLE 13

13 wt-% of the composition of Example 12 and 87 wt-% of polyethylene(Neste, NCPE 2220) were mixed at 150° C. The surface resistance of theresulting blend was 2MΩ.

EXAMPLE 14

20 wt-% of the composition of Example 12 and 80 wt-% of polyethylene(Neste, NCPE 2220) were mixed at 150° C. The surface resistance of theresulting blend was 1MΩ.

EXAMPLE 15

50 wt-% ZnO-DBSA (1:4, w/w) and 50 wt-% PANI-DBSA (mole ratio 1:0.5)were mixed at 150° C. The surface resistance of the composition was500Ω.

EXAMPLE 16

25 wt-% ZnO-DBSA (1:3, w/w) and 75 wt-% PANI-DBSA (1:2.5, w/w) weremixed at 150° C. The surface resistance of the composition was 1kΩ.

EXAMPLE 17

20 wt-% of the composition of Example 16 and 80 wt-% polystyrene (Neste,SB 735) were mixed at 150° C. The surface resistance of the resultingblend was 5MΩ.

EXAMPLE 18

20 wt-% of the composition of Example 16 and 80 wt-% polyethylene(Neste, NCPE 2220) were mixed at 150° C. The surface resistance of theresulting blend was 10MΩ.

Examples 1-18 are summarized in Table 1.

From the blends according to Examples 7-18 testing pieces were preparedin an injection moulding machine. The blends prepared in theseexperiments had by the injection moulding good plasticizing properties,the working trace was good, and the mechanical properties of theproducts closely resembled those of the matrix plastics.

                  TABLE 1                                                         ______________________________________                                               ZnO/     PANI/         Matrix                                                 DBSA     DBSA          poly-                                           Example                                                                              (w/w)    (w/w)   T/°C.                                                                        mer   pH    R                                   ______________________________________                                        1      1:3      1:4     180   PS    7     500 kΩ                               0.8 g    0.8 g         10.4 g                                          2      1:3      1:4     130   No    6-7   100 kΩ                               0.8 g    0.8 g         Matrix                                          3      1:2.7    1:2.5   RT    No    6-7   500 kΩ                               1606 g   1105 g        Matrix                                          4      1:7.2            185   No    6-7   500 kΩ                               2880 g   720 g         Matrix                                          5      1:2.7    1:2.5   170   PS    6-7    30 MΩ                               0.98 g   1.425 g       9.6 g                                           6      1:3      1:1.2   130   No    6-7    30 MΩ                               15 g     15 g          Matrix                                          7      1:3              130   No    6-7    5 MΩ                                15 g     5 g           Matrix                                          8      1:3      1:4     150   No    6-7    3 kΩ                                2.5 g    7.5 g         Matrix                                          9      1:3      1:2.5   150   No    6-7   200 kΩ                               2.0 g    8.0 g         Matrix                                          10     1:3      1:2.5   160   PS    6-7   500 kΩ                               2.0 g    8.0 g         40 g                                            11     1:3      1:2.5   160   PE    6-7   200 kΩ                               2.0 g    8.0 g         30 g                                            12     1:4      1:4     150   No    5-6   200 kΩ                               2.0 g    2.0 g         Matrix                                          13     1:4      1:4     150   PS    5-6    2 MΩ                                2.0 g    2.0 g         27 g                                            14     1:4      1:4     150   PE    5-6    1 MΩ                                2.0 g    2.0 g         16 g                                            15     1:4      1:0.5   150   No    5-6   500 Ω                                2.0 g    2.0 g         Matrix                                          16     1:3      1:2.5   150   No    6-7    1 kΩ                                2.0 g    6.0 g         Matrix                                          17     1:3      1:2.5   150   PS    6-7    5 MΩ                                2.0 g    6.0 g         54 g                                            18     1:3      1:2.5   150   PE    6-7    10 MΩ                        ______________________________________                                    

COMPARATIVE EXAMPLES A-C (OUTSIDE THIS INVENTION) Comparative Example A

An amount of 0.6 g of polyaniline (PANI) (of an inherent viscosity in97% sulfuric acid, at room temperature, in a 0.1% w/w solution of 1.2dl/g), in its conductive salt form with dodecylbenzene sulphonic acid(DBSA), having a molar ratio of PANI(DBSA)₀.5, was mixed with 2.4 g offinely divided powder of isotactic polypropylene (Neste, VB 80 12 B,MFR=8 g/10 min @ 230° C.) using a laboratory-scale twin-screw extruderat 170° C., at 100 rpm for 5 minutes. The resulting polypropylene blendcontained 20 wt-% of the PANI(DBSA)₀.5 complex and had an electricalconductivity of 10⁻⁸ S/cm, as measured by the usual four probetechnique. Small samples of the blend were immersed in water and the pHwas monitored. After 24 hrs the pH of the water was 5.6.

This example illustrates that conductive PANI(DBSA)₀.5 salt could bemelt-blended with thermoplastics to produce an electrically conductingpolymer blend which was only slightly acidic after immersion in waterfor 24 hours. However, the required amount of the PANI salt was high toachieve desirable levels of conductivity, i.e. the percolation thresholdwas higher than 20 wt-%.

Comparative Example B

A total of 3 g of a mixture containing 2.4 g of low density polyethylene(LDPE, Neste, NCE 1804, MI 1.8) and 0.6 grams of PANI(DBSA)₁.1, i.e. aPANI(DBSA)-complex containing an excess amount of DBSA (wt-ratioPANI/DBSA=1/4), was mixed in a laboratory-scale twin-screw extruder at180° C. at 100 rpm for 3.5 minutes. The resulting blend of LDPEcontained 20 wt-% of PANI(DBSA)₁.1 and had a conductivity of 2×10⁻⁴S/cm. Pieces of the blend were immersed in water and the pH wasmonitored. After 24 hrs the pH of the water was pH ˜1.

Comparative Example C

A polymer blend was made according to Example B with the exception thatonly 10 wt-% of PANI(DBSA)₁.1 was used instead of 20%. The conductivityof the resulting blend was 3×10⁻⁷ S/cm. Pieces of the blend wereimmersed in water and the pH was monitored. After 24 hrs the pH of thewater was pH ˜1.

Comparative Examples B and C demonstrate that electrically conductingpolymer blends could be produced using thermoplastics and PANI(DBSA)₁.1utilizing conventional melt processing techniques. The examples furtherdemonstrate, however, that addition of an excess amount of DBSA to thePANI-salt order to lower the percolation threshold of the conductivity.However, due to the large amount of free acid in the blend, the acidityof the final product was unacceptably high.

EXAMPLE 19

ZnO powder and liquid DBSA, using different molar ratios ranging from1:1-1:8, were mixed between 130°-180° C. During the reaction, water wasliberated under the formation of a complex between ZnO and DBSA,suggesting the formation of the structure denoted Zn(DBS)₂. This solidcomplex had a melting temperature of ca. 115° C., was observed to beliquid crystalline and of fiber forming characteristics, in addition ofbeing non-conducting. For simplicity, in subsequent examples, thisreaction product will be referred to as Zn(DBS)₂.

EXAMPLE 20

An amount of 2.7 g of LDPE, 0.3 g of PANI(DBSA)0.5 and 0.86 g of theZn(DBS)₂ material prepared according to the method of Example 19 suchthat the molar ratio Zn(DBS)_(2/) PANI(DBSA)₀.5 =1.0, were mixed in atwin-screw extruder for 3.5 minutes at 180° C. at 100 rpm. Theconductivity of the resulting polymer blend, containing 7.8 wt-% ofPANI(DBSA), had a four probe conductivity of 8×10⁻² S/cm. Pieces of theblend were immersed in water and the pH was monitored. After 24 hrs thepH of the water was pH ˜4.

EXAMPLES 21-25

Blends were made according to Example 20 but with different amounts ofPANI(DBSA)₀.5. The ratio of Zn(DBS)_(2/) PANI(DBSA)₀.5 was maintained at1.0. The conductivities of the resulting polymer blends were measuredand are listed in Table 2 below.

                  TABLE 2                                                         ______________________________________                                        Example wt-% PANI(DBSA).sub.0.5                                                                       Conductivity (S/cm)                                   ______________________________________                                        21      2.3             4 × 10.sup.-5                                   22      3.2             2 × 10.sup.-3                                   23      4.4             3 × 10.sup.-2                                   24      7.8             8 × 10.sup.-2                                   25      12.8            2 × 10.sup.-1                                   ______________________________________                                    

EXAMPLE 26

An amount of 2.7 g of isotactic polypropylene (i-PP, Neste, VB 80 12 B),0.3 g of PANI(DBSA)₀.5 and 0.86 g of Zn(DBS)₂, prepared according toExample 19, were mixed in a twin-screw extruder at 170° C., at 100 rpmfor 5 minutes. The resulting polymer blend, containing 7.8 wt-%PANI(DBSA)₀.5 of the total composition of the blend, had a four probeconductivity of 2×10⁻² S/cm. Pieces of the blend were immersed in waterand the pH was monitored. After 24 hrs the pH of the water was pH ˜4.

EXAMPLES 27-31

Blends were made according to Example 26 but with different the amountsof PANI(DBSA)₀.5. The ratio of Zn(DBS)_(2/) PANI(DBSA)₀.5 was varied.The conductivities of the resulting polymer blends were measured and arelisted in Table 3 below.

                  TABLE 3                                                         ______________________________________                                        Example wt-% PANI(DBSA).sub.0.5                                                                       Conductivity (S/cm)                                   ______________________________________                                        27      3.2             4 × 10.sup.-6                                   28      4.4             2 × 10.sup.-3                                   29      7.8             2 × 10.sup.-2                                   30      12.8            6 × 10.sup.-2                                   31      21.0            2 × 10.sup.-1                                   ______________________________________                                    

EXAMPLE 32

An amount of 2.7 g polystyrene (Neste, SB 735), 0.3 g PANI(DBSA)₀.5 and0.86 g of Zn(DBS)₂, prepared according to example 1, were mixed in atwin-screw extruder at 190° C. at 100 rpm for 5 minutes. The resultingpolymer blend, containing 7.8 wt-% of PANI(DBSA)₀.5 of the totalcomposition of the blend, had a four probe conductivity of 2×10⁻² S/cm.Pieces of the blend were immersed in water and the pH was monitored.After 24 hrs the pH of the water was pH ˜5.

EXAMPLE 33-37

Blends were prepared according to Example 14 but with different theamounts of PANI(DBSA)₀.5. The ratio of Zn(DBS)_(2/) PANI(DBSA)₀.5 wasmaintained at 1.0. The conductivities of the resulting polymer blendswere measured and are listed in Table 4 below.

                  TABLE 4                                                         ______________________________________                                        Example  wt-% PANI(DBSA)                                                                              Conductivity (S/cm)                                   ______________________________________                                        33      2.3             8 × 10.sup.-7                                   34      3.2             5 × 10.sup.-6                                   35      4.4             8 × 10.sup.-4                                   36      7.8             2 × 10.sup.-3                                   37      12.8            2 × 10.sup.-2                                   ______________________________________                                    

Examples 20-37 and Tables 2-4 demonstrate that by the addition ofZn(DBS)₂ to a mixture of a common thermoplastic commodity polymer andPANI(DBSA)₀.5, polymer blends could be produced, using ordinary meltprocessing techniques, that exhibited surprisingly lower percolationthresholds for electrical conductivity (1-3 wt-% of the conductingpolyaniline complex) than observed in blends produced without theaddition of the Zn(DBS)₂.

EXAMPLE 38

A polymer blend was made according to example 2 with the exception thatinstead of ZnO, CuO (Aldrich) was used as the metal compound. Theresulting blend was electrically conducting, the four point conductivitybeing 10⁻⁵ S/cm.

Example 20 demonstrate that also other metal compounds than ZnO could beused to form a condensation product with a protonic acid that acted as apercolation-threshold reducing agent.

EXAMPLE 39

A polymer blend was made according to example 2 with the exception thatinstead of DBSA, ethylsulfonic acid (ESA, Aldrich) was used as theprotonic acid. The resulting blend was electrically conducting and thefour point conductivity was measured to be 10⁻⁴ S/cm.

EXAMPLE 40

7.17 g of Zn(DBS)₂ was mixed with 1.7 g of conducting polyanilinecompound (Versicon™, Allied-Signal) for 5 minutes at 130° C. in aconical twin-screw extruder. 0.355 g of the obtained mixture, 0.717 g ofadditional Zn(DBS)₂ and 2.328 of acrylonitrile-butadiene-styrene (ABS)were mixed in the same extruder at 160° C. for 5 minutes. Theconductivity of films of the above blend, pressed at 180° C., was8.3×10⁻² S/cm, containing only 2 wt-% of the conducting componentVersicon™.

Comparative Example D (outside this invention)

Example 1 was repeated, but instead of DBSA, p-toluene sulphonic acid(TSA, Aldrich) was used. Mixing of ZnO and TSA resulted in the formationof a white powder that did not display an melting point below 300° C. Apolymer blend was made according to Example 2 with the exception thatinstead of Zn(DBS)₂, the above condensation product of ZnO and TSA wasused. The resulting blend was nonconducting and optical microscopyshowed that the blend comprised of dispersed particles of thecondensation product.

Comparative Example E (outside this invention)

A polymer blend was made according to Example 20 with the exception thatinstead of Zn(DBS)₂, the common, commercial plasticizers, pentadecylphenol and dodecylphenol (Aldrich) were used. The blends, although wellplasticized, were nonconducting.

This example illustrates that the use of the aforementioned condensationproducts of metal compounds, preferably ZnO, and protonic acids indeedwere unusually effective in functioning as a neutralization,plasticization and percolation-threshold reducing agents, which was notobserved in the use of the common plasticizers as those employed inExample 39.

We claim:
 1. Method for making an electrically conductive polymercomposition, the electrically conductive polymer composition comprisingan admixture of:(a) a complex having an electrical conductivity of atleast about 10⁻⁶ S/cm, of:(i) a conjugated polymer, having substitutedor unsubstituted aniline repeating units and being selected from thegroup consisting of polyaniline, substituted polyanilines, or copolymersthereof; and (ii) a first protonic acid, the first protonic acid beingselected to impart said electrical conductivity to said conjugatedpolymer; (b) a reaction product having a softening temperature of belowabout 300° C., of (1) a metal compound MX wherein M is selected from thegroup consisting of Zn, Cu, Mg, Ba, Al, Ca, Ti, Fe, Zr, Cd, Pb and Sn,and X is selected from the group consisting of oxides, hydroxides,halides, stearates, carbonates, palmitates, octoates, laurates,phenolares, maleares, and octylthioglycolates, and (2) a second protonicacid, which may be the same or different from the first protonic acid ofsaid complex, having a structural formula I-II: ##STR2## wherein: "A" issulfonic acid, selenic acid, phosphonic acid, boric acid or a carboxylicacid group; or hydrogen sulphate, hydrogen selenate or hydrogenphosphate; "n" is an integer in the range of 0-5 inclusive; "m" is aninteger in the range of 0-4 inclusive, with the proviso that the sum ofn+m is 5; "R₁ " is an alkyl, alkenyl, alkoxy, alkanoyl, alkylthio,alkylthioalkyl containing 1-20 carbon atoms; or alkylaryl, arylalkyl,alkylsulphinyl, alkoxyalkyl, alkylsulphonyl, alkoxycarbonyl, carboxylicacid, where the alkyl or alkoxy has from 0 to about 20 carbon atoms; oralkyl having from 3-20 carbon atoms substituted with one or moresulfonic acid, carboxylic acid, halogen, nitro, cyano, diazo or epoxymoieties; or a substituted or unsubstituted 3, 4, 5, 6, or 7 memberedalicyclic carbon ring, which ring may include one or more divalentheteroatoms of nitrogen, sulfur, sulfinyl, sulfonyl or oxygen such asthiophenyl, pyrolyl, furanyl, pyridinyl; or a polymeric backbone towhich A units are attached; R is the same or different at eachoccurrence and is an alkyl, alkenyl, alkoxy, cycloalkyl, cycloalkenyl,alkanoyl, alkylthio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,alkylsulphinyl, alkoxyalkyl, alkylsulphonyl, aryl, arylthio,arylsulphinyl, alkoxycarbonyl, arylsulphonyl, carboxylic acid, halogen,cyano, or alkyl which has been substituted with one or more sulfonicacid, carboxylic acid, halogen, nitro, cyano, diazo or epoxy moieties;or any two R substituents taken together are an alkylene or alkenylenegroup completing a 3, 4, 5, 6 or 7 membered aromatic or alicyclic carbonring or multiples thereof, which ring or rings may include one or moredivalent heteroatoms of nitrogen, sulfur, sulfinyl, sulfonyl or oxygen,with R typically having from 1 to about 20 carbons; said methodcomprising contacting said metal compound MX with a mixture comprisingsaid electrically conductive complex of said conjugated polymer and saidfirst protonic acid and said second protonic acid wherein the molarratio between the acidic protons of said first protonic acid and theaniline repeat units of said conjugated polymer is at least about 0.5;and wherein said metal compound MX reacts with the excess of said firstand second protonic acids to yield a reaction product of said metalcompound and said first and second protonic acids; wherein said reactionproduct neutralizes and plasticizes said electrically conductive polymercomposition.
 2. Method according to claim 1, wherein said contacting iscarried out at temperatures in the range from at least about 40° C. toless than 300° C.
 3. Method according to claim 2, wherein saidcontacting carried out at temperatures in the range from at least about50° C. to less than about 250° C.
 4. Method for making the compositionof claim 1, wherein a substantially nonconductive substrate is added tothe polymer composition.
 5. Method for making the electricallyconductive polymer composition of claim 1, wherein the metal compound MXis ZnO.
 6. Method for making the electrically conductive polymercomposition of claim 1, wherein said reaction product is formed betweenZnO and dodecylbenzene sulphonic acid.
 7. Method for making theelectrically conductive polymer composition of claim 1, wherein thecomposition has a pH of 3 to
 8. 8. Method for making an electricallyconductive polymer composition, the electrically conductive polymercomposition comprising an admixture of:(a) a complex having anelectrical conductivity of at least about 10⁻⁶ s/cm, of:(i) a conjugatedpolymer, having substituted or unsubstituted aniline repeating units andbeing selected from the group consisting of polyaniline, substitutedpolyanilines, or copolymers thereof; and (ii) a first protonic acid, thefirst protonic acid being selected to impart said electricalconductivity to said conjugated polymer; (b) a reaction product having asoftening temperature of below about 300°°C., of (1) a metal compound MXwherein M is selected from the group consisting of Zn, Cu, Mg, Ba, Al,Ca, Ti, Fe, Zr, Cd, Pb and Sn, and X is selected from the groupconsisting of oxides, hydroxides, halides, stearates, carbonates,palmitates, octoates, laurates, phenolates, maleates, andoctylthioglycolates, and (3) a second protonic acid, which may be thesame or different from the protonic acid of said complex, having astructural formula I-II: ##STR3## wherein: "A" is sulfonic acid, selenicacid, phosphonic acid, boric acid or a carboxylic acid group; orhydrogen sulphate, hydrogen selenate or hydrogen phosphate; "n" is aninteger in the range of 0-5 inclusive; "m" is an integer in the range of0-4 inclusive, with the proviso that the sum of n+m is 5; "R₁ " is analkyl, alkenyl, alkoxy, alkanoyl, alkylthio, alkylthioalkyl containing1-20 carbon atoms; or alkylaryl, arylalkyl, alkylsulphinyl, alkoxyalkyl,alkylsulphonyl alkoxycarbonyl, carboxylic acid, where the alkyl oralkoxy has from 0 to about 20 carbon atoms; or alkyl having from 3-20carbon atoms substituted with one or more sulfonic acid, carboxylicacid, halogen, nitro, cyano, diazo or epoxy moieties; or a substitutedor unsubstituted 3, 4, 5, 6 or 7 membered alicyclic carbon ring, whichring may include one or more divalent heteroatoms of nitrogen, sulfur,sulfinyl, sulfonyl or oxygen such as thiophenyl, pyrolyl, furanyl,pyridinyl; or a polymeric backbone to which A units are attached; R isthe same or different at each occurrence and is an alkyl, alkenyl,alkoxy, cycloalkyl, cycloalkenyl, alkanoyl, alkylthio, aryloxy,alkylthioalkyl, alkylaryl, arylalkyl, alkylsulphinyl, alkoxyalkyl,alkylsulphonyl, aryl, arylthio, arylsulphinyl, alkoxycarbonyl,arylsulphonyl, carboxylic acid, halogen, cyano, or alkyl which has beensubstituted with one or more sulfonic acid, carboxylic acid, halogen,nitro, cyano, diazo or epoxy moieties; or any two R substituents takentogether are an alkylene or alkenylene group completing a 3, 4, 5, 6 or7 membered aromatic of alicyclic carbon ring or multiples thereof, whichring or rings may include one or more divalent heteroatoms of nitrogen,sulfur, sulfinyl, sulfonyl or oxygen, with R typically having from 1 toabout 20 carbons; said method comprising reacting said metal compound MXwith said second protonic acid to form said reaction product, andsubsequently mixing said reaction product with said electricallyconductive complex of said conjugated polymer and said first protonicacid and, wherein the molar ratio between the acidic protons of saidfirst protonic acid and the aniline repeat units of said conjugatedpolymer is at least about 0.5; wherein said reaction product neutralizesand plasticizes said electrically conductive polymer composition. 9.Method for making the composition of claim 8, wherein the compositionfurther comprises a substantially nonconductive substrate.
 10. Methodfor making the composition of claim 8, wherein said metal compound isfirst reacted with said second protonic acid to yield an approximatelyneutral or slightly acidic reaction product that is subsequently mixedwith said electrically conductive complex of said conjugated polymer andsaid first protonic acid, wherein the molar ratio between the acidicprotons of said first protonic acid and the aniline repeat units of saidconjugated polymer is at least from about 0.2 to less than about 0.5;and wherein said reaction product plasticizes said composition.
 11. Amethod for making the composition of claim 9, wherein said metalcompound is first reacted with said second protonic acid to yield anapproximately neutral or slightly acidic reaction product that issubsequently mixed with said substantially nonconductive substrate andsaid electrically conductive complex of said conjugated polymer and saidfirst protonic acid, wherein the molar ratio between the acidic protonsof said first protonic acid and the aniline repeat units of saidconjugated polymer is at least from about 0.2 to less than about 0.5;and wherein said reaction product plasticizes said composition andreduces the percolation threshold for electrical conductivity in saidpolymer composition.
 12. Method for making the composition of claim 8,wherein said metal compound is first reacted with an excess of saidsecond protonic acid to yield an acidic reaction product that issubsequently mixed with the complex of said conjugated polymer and saidfirst protonic acid, wherein the molar ratio between the acidic protonsof said first protonic acid and the aniline repeat units of saidconjugated polymer is in the range from 0 to less than about 0.2, so asto yield an approximately neutral or slightly acidic composition; andwherein said reaction products plasticize said composition.
 13. Methodfor making the composition of claim 9, wherein said metal compound isfirst reacted with an excess of said second protonic acid to yield anacidic reaction product that is subsequently mixed with saidsubstantially nonconductive substrate and with the complex of saidconjugated polymer and said first protonic acid, wherein the molarration between the acidic protons of said first protonic acid and theaniline repeat units of said conjugated polymer is in the range from 0to less than about 0.2, so as to yield an approximately neutral orslightly acidic composition; and wherein said reaction productplasticizes said composition and reduces the percolation threshold forelectrical conductivity in said polymer composition.